Loud vibration around 40mph (1 Viewer)

[cruisergear]

just took it by a well established driveshaft shop today. I asked them if a Double Cardan shaft would get rid of my vibrations and got a whole lot of
"why would you want that"
"you don't know anything, we're the experts"
"and what you need to do is CLOCK YOUR PINION UP to get the ujoint at it's optimal operating angle"

wtf.....

I asked them repeatedly if driveshafts ends were supposed to be on parallel planes and they repeatedly said "no you don't want to clock your pinion down. That will put strain on your ujoint. you want to clock your pinion up so that the joint is almost perfectly straight."

They didn't care that the joint on the t-case side is making like a 5 degree bend. They just wanted the joint on the pinion of the driveshaft straight as possible. SMH...

 

[too tall]

A double cardan shaft might work just fine . Your pinion is pointing at the t-case . I haven't had very good luck with them behind a v-8 . I find the smaller u-joints wear out faster with bigger horsepower. It would probably take care of your issues . If you were closer , I'd give you one to try .

 

[cruisergear]

Thanks Too Tall! I'm going to get a front double cardan from a FJ60 and then have a driveshaft shop lengthen it for the rear end. Hopefully I'll be able to do that at the same time I rebuild my thirds with a re-gear so it will all be in ship shape. fingers crossed.

 

[Output Shaft]

I've had very bad luck getting correct information from driveshaft shops regarding the land cruiser. To the point I'm convinced that they (the shops I visited at least) don't know what they're talking about. Depressing.

 

[tmxmotorsports]

@cruisergear I have had a vibration in my 62. I have rebuilt the tcase still have the vibration my 62 has ome heavy front and rear also has shackle reversal and long shackles in the back. I just ordered 6 degree steel shims from 4wheel parts they should be here in a couple days. I also replaced my ujoints not long after I got the truck that didn't fix it my tcase was leaking and had play in the rear output shaft diff is tight and doesn't leak. Just thought I would add to your thread instead of starting another. The angle of the drive shaft isn't bad really don't think a cv is necessary. My pinion is pointed up towards the tcase because of the longer shackles. Hope you get yours figured out.

 

[tmxmotorsports]

And the diagram that is posted in this thread is correct. When I set up @Str8Razor fj60 with the vortec nv4500 205 and centered currie 9inch it is set up no cv and has more angle than my 62.

 

[tmxmotorsports]

I got the 6 degree shims still vibrates damnit!

 

[too tall]

I got the 6 degree shims still vibrates damnit!

maybe you should post a pic of your setup. from the side showing the angles would be good.

 

[Tin basher]

You did install the shims between the diff and springs
Not the spring and u bolt plate right ?
I have had a 40 come to me from a suspension shop like that
You have the wedge shaped shim thick side to front right ?
Tipping pinion up correct ?
Try flipping them around and I bet the shake decreases or goes away
Having the pinion aimed straight with driveshaft is
For a double cardan joint not a single u joint

 

[Tin basher]

Maybe this should clairify it on the single joint your angles should match being as how your t case is 1 deg up and your pinion was 5 deg up and is now 11 deg you are now like this worse \ / than you started
So by flipping the shims around you will be parallel \\Not ideal but shouldn't vibrate rollin down the road d

 

[tmxmotorsports]

I can't post pics right now. @Tin basher . My pinion was pointed up towards the tcase 6 degree and yes they are installed correctly the thick side in the back my truck is sprung under if I installed it the way you say it would point the pinon up towards the tcase I have the factory drive shaft no cv my drive flanges are at the same angle now but it actually vibrates a little more. Also before I installed the shims my drive shaft had very little movement left in the slip spline now it has more movement with the pinion pointed down. I have the long ome shackles in the back and shackel reversal in front. Everything that is done to the 62 the po had it installed found out that the center pin adapters we not installed so I found one of the ones from another 60 I lifted that i put a currie 9 inch in I had to turn another one down on the lathe. So the rear end was offset to one side and crooked I also found out that the driver side has cs004ra spring and the passenger has cs005rb truck does sit level but one is a medium and one is a heavy haven't counted the spring pack or taken any measurements when I took it for a test drive it still vibrated so drove straight to the bar for some beers haven't touched it after that. After all the lifted trucks I have owned and built this is the smallest and least amount of drive line angels.

 

[cruisergear]

TMX
Sounds like we have similar setups besides my engine/tranny. But the lifts sound the same. I'm glad you were able to try shims as I really didn't want to lol. I'm rebuilding my thirds in a few weeks (to do 4.88 gears and lockers, not for vibrations), so when i've got it all torn apart i'm going to throw a double cardan driveshaft on the rear as well. there's really nothing left at that point so it really should get rid of the vibration lol.

good luck with yours as well!

 

[Tin basher]

I think you should replace the u joints
With them being ran that long with the shaft vibrating like that
I bet the bearing surfaces on the u joints is no longer smooth and round because the ujoints have Been going through a bind every revolution
The dc might cure it and it might not
But it's going to cost you a couple hundred bucks to lengthen the dc driveshaft +what you pay for driveshaft
I bet you could get The engine angle fixed for less
Depending on how the mounts are done could cost
A couple bucks in washers to raise front of motor
Or lower back of trans with simple hand tools
That 1.4 deg up you have on the trans output is the problem the angles are parallel but the drive angle is wrong pointing away from each other than towards this might help you understand what's causing it th

 

[tmxmotorsports]

@Tin basher I already changed the ujoints my setup is factory fj62

 

[cruisergear]

@Tin basher thanks, i've seen that video. That's the video that lead me to decide i need a double cardan haha. And luckily, I've got a DC driveshaft for free from a friend so i'm not too worried about the cost to try a DC on the rear.

The rear-most ujoint in my current driveshaft is definitely in need of replacing. but I'm not gonna replace the ujoints on my existing driveshaft before trying a DC because the existing driveshaft (u-joints included) was brand new and custom made for our LC when we installed it after the lift/motor swap. And day 1 we had vibrations. So i do not believe the bad u-joint is the cause of the vibrations, but instead a symptom of the vibration.

I should have provided more context to the 1.4 and -5.6 degree measurements. That was not on flat ground so i can't actually say for sure if the transfer case/tranny/motor are mounted incorrectly. The 1.4 degree measurement is probably from a slope on our driveway. I merely wanted to know the difference between the t-case output and the pinion so i wasn't worried about parking on flat ground. (Subtracting the two i got the difference of 7*). But I could see how raising the engine would lessen the difference to less than 7*, but at the same time it would be making the front driveshaft angles worse so i'd rather not go that route until i know for sure if the DC fixes it or not.

 

[tmxmotorsports]

I have a mini truck cv shaft from one of my other trucks that I never used and another lc shaft that I cut down to make the front shaft on @Str8Razor 60 build I also have a couple 4runner rear shafts for the tubing but before I do all of that I am going to check a couple other things.

 

[tmxmotorsports]

Sorry @cruisergear not trying to hyjack your thread

 

[Tin basher]

@cruisergear you shouldn't need a dc driveshaft in that though will it work yes probably but it's sort of a bandaid fix
Jeeps use them because the driveshaft is so short
They have to tip the pinion up because the u joints are close to bind

Your angles should be almost parellel now right
Is the shake worse under acceleration Or under deceleration? If acceleration the pinion needs to go down more if on deceleration it needs to go up
A trashed u joint will cause a constant rumble
Is that drive shaft in phase ? That can do it to
Yes I've seen them wrong from a driveshaft place
What points more to the engine angle being wrong
Is many people use that same spring and shackle combo and don't have a problem
Have you checked your angles now ?
I go off the bottom of the frame for level Take that angle and add or subtract from the pinion t case angle
have you fixed the pinion bearing yet ?
Just had a thought the motor isn't in crooked is it ?
Easiest way to check is clamp a straight edge on the pinion and t case output facing across the chassis
Measure and see if it's same on either side of output

 

[too tall]

Tin Basher, Not sure if you realize it, but toyota put quite a few of their engines in crooked from factory. I wouldn't waste time measuring that part. I have also found that a few degrees out in any direction won't have a great effect. As you mentioned, acceleration and deceleration will give you clues if your pinion angle gets better with shimming it either way. If you are close to what the angles should be then you may have issues other than pinion alignment.

 

[cruisergear]

@tmxmotorsports generally i wouldn't care but i can't tell if people are replying to me or to you. And since we don't have the same motor/tranny, our solutions may be different. If skimming through the thread they might mistake information you provide about your setup to be from me and give me incorrect advice.

It would help both you and I if you had your own thread. I don't care if you use this thread once i get my issue resolved though. thanks for understanding!